This invention relates to molecular sieves for use in oxygen concentrators and a novel container for use therewith.
More particularly, the invention is concerned with a container having a tubular body and provided with end caps which are seam welded to the tubular body to prevent leakage as well as to assist in the maintenance of the position of the sieve material in the container. The ports of entry and outlet to and from the container are also seam welded to prevent leakage. The oxygen concentrators are primarily intended for home use, so that long life is of extreme importance, as well as to have the ability to be free-standing. The molecular sieve is intended for an oxygen concentrator which is primarily intended for supplying pure oxygen to a patient to breathe and for recharging in the field.
A molecular sieve is a filter comprising a material which has a high affinity for one or more particular gases and therefore can remove such gases by adsorption, thus concentrating the remaining gas or gases.
It is important to prevent the sieve material from moving around in the container in order to ensure an even gas flow. Therefore, alignment of the sieve material is an important requirement, and avoidance of a by-pass around the sieve material is important.
Molecular sieves are used in two main fields. One of these is for large scale, heavy duty preparation of fluids, requiring expensive apparatus and often producing extremely high purities, perhaps of the order of 99.9999% pure. Examples are the preparation of purified atmosphere for use in the manufacture of semi-conductor devices or for spacecraft research. The other main field is for personal use, as for oxygen concentrators, wherein ordinary air is passed through a molecular sieve to adsorb the nitrogen and leave perhaps 95% pure oxygen for a medical patient to breathe. The sieves in this field tend to be much cheaper and smaller.